Mia says that every time she lifts weights, she builds muscle by tearing and rebuilding muscle fibers. Which type of contraction is the MOST efficient at breaking down and building up muscle?

Eccentric contractions occur when a muscle lengthens while resisting a load, such as lowering a weight. This phase places high tension on the muscle and is especially effective at creating the microscopic muscle-fiber damage that is repaired during recovery. Concentric contractions shorten the muscle as it lifts the weight, while the other choices describe different muscle concepts rather than contraction types.

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